Novel Prospects of the Acidic Thermal Rearrangement of Spiro[cyclopropane-1,5′-isoxazolidines] toβ-Lactams
作者:Franca M. Cordero、Maria Salvati、Federica Pisaneschi、Alberto Brandi
DOI:10.1002/ejoc.200300595
日期:2004.5
Monocyclic β-lactams were synthesized by a 1,3-cycloaddition/thermal rearrangement process in the presence of a protic acid, starting from methylenecyclopropane derivatives and acyclic nitrones. Five-membered cyclic nitrones failed to give carbapenam structures under the same conditions, affording exclusively the corresponding N-trifluoroacetyl β-amino acid derivatives in the presence of trifluoroacetic